<template>
  <header class="header">
    <h1>todos</h1>
    <input id="toggle-all" class="toggle-all" type="checkbox" v-model="isAll"/>
    <label for="toggle-all"></label>
    <input
      class="new-todo"
      placeholder="输入任务名称-回车确认"
      autofocus
      v-model.trim="content"
      @keyup.enter="add"
    />
  </header>
</template>

<script>
export default {
  props:['arr'],
  data() {
    return {
      content: "",
    };
  },
  methods: {
    add() {
      if (this.content.length === 0) {
        return alert("内容不能为空");
      }
      this.$emit("add", this.content);
      this.content = "";
    },
  },
  	computed:{
			isAll:{
				set(checked){
					this.arr.forEach(item=>item.isDone=checked)
				},
				get(){
					if(this.arr.length===0){
						return false
					}
					return this.arr.length!==0 && this.arr.every(item=>item.isDone)
				}
			}
		}
};
</script>
